/Engine/Plugins/Runtime/MassGameplay/Source/MassLOD/Public/MassLODSubsystem.h
Returns viewer handle from the streaming source name
[FMassViewerHandle](API\Plugins\MassLOD\FMassViewerHandle) GetViewerHandleFromStreamingSource ( const [FName](API\Runtime\Core\UObject\FName) StreamingSourceName ) const